DLH Executive and Leadership Team

June, 2026

Leadership Overview

DLH has 4 executives leading key functions including strategy, finance, public health, and operations.

Driven by innovation, DLH provides technology-enabled business process outsourcing, program management solutions, and public health research and analytics services, impacting national health and defense sectors.

Leadership Roles at DLH

  • President & Chief Executive Officer - Zachary Parker
  • Chief Financial Officer - Kathryn JohnBull
  • President - Mary Dowdall
  • Chief Medical Officer, Dlh Corporate - Joseph Martin
  • Zachary Parker - President & Chief Executive Officer

    Zachary Parker, the President & Chief Executive Officer at DLH, directs the company's overall strategic vision and operational execution. Parker guides DLH's technology-enabled business process outsourcing, program management solutions, and public health research and analytics services across the United States. This leadership involves driving digital transformation and cybersecurity initiatives, including the integration of artificial intelligence and machine learning, cloud enablement, and big data analytics. Parker ensures alignment with the needs of major clients such as the National Institutes of Health (NIH) and the Defense Health Agency. The President & Chief Executive Officer oversees the expansion of DLH's market presence by fostering innovation and delivering advanced solutions. Zachary Parker's focus remains on enhancing the company's capabilities to meet complex government and public health challenges, securing sustained growth and operational excellence.

    Kathryn JohnBull - Chief Financial Officer

    Kathryn JohnBull, the Chief Financial Officer at DLH, manages the company's financial strategy and fiscal operations. JohnBull oversees all aspects of financial planning, budgeting, and reporting, ensuring the fiscal health and stability of DLH's diverse service offerings. This role is critical in supporting the company's technology-enabled business process outsourcing, program management, and public health research and analytics services. The Chief Financial Officer works closely with other executive leaders to allocate resources effectively, driving profitability and shareholder value. JohnBull's responsibilities include managing financial risk, optimizing capital structure, and ensuring compliance with all relevant financial regulations. Kathryn JohnBull's financial acumen is essential for sustaining DLH's growth trajectory and supporting its mission-critical government contracts, particularly within the defense and public health sectors.

    Mary Dowdall - President

    Mary Dowdall, the President at DLH, drives operational excellence and strategic growth across key business segments. Dowdall oversees the delivery of technology-enabled business process outsourcing and program management solutions, ensuring seamless execution for government clients. This leadership position involves managing complex projects and fostering strong client relationships, particularly with entities like the US Navy Naval Information Warfare Center (NIWC). The President focuses on enhancing DLH's capabilities in digital transformation and cybersecurity, including artificial intelligence and big data analytics. Mary Dowdall's operational oversight is vital for maintaining high standards of service and expanding the company's footprint in critical technology and public health sectors. Dowdall's strategic direction supports DLH's mission to provide impactful solutions that address national challenges.
    Mary Dowdall

    Joseph Martin - Chief Medical Officer, Dlh Corporate

    Joseph Martin, the Chief Medical Officer, Dlh Corporate at DLH, provides critical medical and public health expertise to guide the company's service development and delivery. Martin oversees the strategic direction of DLH's public health research and analytics services, ensuring scientific rigor and clinical relevance. This leadership role is pivotal in shaping solutions for clients like the National Institutes of Health (NIH) and the Defense Health Agency, focusing on areas such as telemedicine and advanced research. The Chief Medical Officer, Dlh Corporate ensures that DLH's offerings in digital transformation and cybersecurity align with the evolving needs of the healthcare and public health landscape. Joseph Martin's insights are crucial for enhancing the impact of DLH's program management solutions and technology-enabled services, driving better health outcomes through data-driven analytics and research.

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    Frequently Asked Questions Regarding DLH Top Executives and Leadership Team

    Who leads DLH?
    DLH is led by Zachary Parker (President & Chief Executive Officer), along with executives such as Kathryn JohnBull (Chief Financial Officer) and Mary Dowdall (President).
    Who is part of DLH’s executive team?
    The executive team of DLH includes leaders such as Zachary Parker (President & Chief Executive Officer), Kathryn JohnBull (Chief Financial Officer), Mary Dowdall (President) and other senior executives.
    How many executives does DLH have?
    DLH has 4 executives leading key business areas.
    What roles are included in DLH’s leadership team?
    The leadership team of DLH includes roles such as President & Chief Executive Officer, Chief Financial Officer, President, Chief Medical Officer, Dlh Corporate.